What is the difference between Google Service Framework(GSF)&Google Mobile Service(GMS)?

Question

I am learning Google Cloud Message recently, it requires both GSF and GMS(which new name is Google Play Service, but not that Google Play app). I decompile the code of both, but I don't know the usage of them, and don't know why Google provider these two services, why not one? And what's the difference of them?

Answer 1

I think it would be good to define them first:

-Google Mobile Services (GMS) is a collection of Google applications and APIs that help support functionality across devices. Samples are Gmail, Chrome, Google+, Google Maps and Youtube.

-Google Play Services(Google Service Freamwork) is used to make sure that everything is running smoothly on your device.

It takes care of the following:

1.Google Backup

2.Play Store Services

3.Contacts Sync

4.Account Manager